Cryptocurrency Price Plunge, why did it happen and the danger of Bitcoin ETF

Within the last 24 hours, Bitcoin has seen a price drop of almost 1,000 points, representing a more than 10% plunge since the Bitcoin ETF once again was rejected. This was an expected event and I think the bears that were just waiting for excuse to sell and dip the price took this as a reason to do so. However, if you look at the sell-off pattern in the last day, it wasn’t gradually decreasing throughout the day. It was comprised of sudden sell-offs that happened within 5 or 10 minutes, then the price would stabilize for a few hours before another sudden sell-off. This indicates to me the possibility of coordinated sells or coordinated short-sells, which would qualify as market manipulation and would be illegal. I actually think the addition of futures last December has been horrible for Bitcoin and the cryptocurrency market overall. One of the main reasons is that the contracts are settled in cash when they should be settled in Bitcoin. Being settled in cash lets you make double profit by going long on actual Bitcoin and shorting Bitcoin futures. You short the futures to tank the price and then buy Bitcoin when its low and make money when the price recovers. It is very vulnerable to coordinated short-sells by large buyers in the market. Futures contracts should be settled in their native cryptocurrency instead of cash.
This brings me to the dangers long-term of the Bitcoin ETF fund precisely because you can actually short the ETF. I think unscrupulous wall-street types will take this opportunity to short-sell the ETF and tank the price for their own benefit and since there is little regulation regarding this behavior, it could cause massive flux in the Bitcoin markets to further erode confidence.
I think most of these issues could be solved if futures contracts were resolved in their native Crypto instead of cash so if people purposely tank the price of a crypto, then when their contracts are settled, they get the de-valued asset instead of cash. There needs to be some regulation in futures market because you don’t actually have to buy or sell actual crypto to be in the game and that opens it up to massive amounts of manipulation.